Apoptosis Of Sacroiliac Neural Tube In Rat Embryos With Neural Tube Defects(NTDs)

Neural tube defects (Neural tube defects, NTDs) are one of the most common serious central nervous system congenital malformations, an incidence rate of 0.1% of the world average, ranking first in the world, China's incidence rate is about 0.129%. Therefore, the embryogenesis of NTDs in-depth study play a necessary role in its effective prevention. In recent years, it has been studied extensively in the cellular, sub-cellular and molecular level for the mechanism of NTDs, recently,the more common option is that, most NTDs are due to the interaction of internal factors (genetic factors) and environmental factors (teratogenic factors). However, the exact causes of NTDs is not known clearly, pathological changes is complex, and there has no adequate prevention and treatment measures. Therefore, the study of the occurrence of these abnormal embryos and early diagnostic methods which provides a necessary pre-foundation to prevention and early treatment of malformations, and has a great significance to reduce birth defects, improve the quality of the population.Apoptosis is a widespread physiological phenomenon in the development of the central nervous system as well as the formation, a variety of mechanism to prevent excessive apoptosis of cells, such as the regulation of cell systems as well as neurotrophic factor from the neural derived cells and glial cells. Any element of these mechanisms is defected or damaged that will cause excessive apoptosis, which will lead to the occurrence of neural tube defects.Therefore, this study will use TUNEL assay to study the changes of apoptosis in different stages of embryonic development with neural tube defects, to explore the mechanism of neural tube defects.Methods 1. The establishment of embryo model of NTDs1.1 Divide randomly 10d pregnant rats into control group and experimental group, make up the model:use the gavage method, according to body weight, give retinoic acid (RA)150mg/Kg to experimental rats, while the control group was given a corresponding volume of olive oil.1.2 Dissect uterus and then remove embryos during pregnant 11d,12d,13d.2. Difference analysis between embryos with NTDs and the control group2.1 Make paraffin sections of the two groups.2.2 Stain the paraffin section use the TUNEL kit, than compared two groups of slices.Results1. Produce successfully rat embryos model of neural tube defects.2. Difference analysis of apoptosis between Retinoic acid group and the control group:There has statistical significance among the three groups.ConclusionRetinoic acid can be produced successfully an animal model of neural tube defects, excessive apoptosis of neuroepithelium in E11 and E12 embryos is the important reason that cause neural tube defects.